Antifoam compositions for automatic transmission fluids contain antifoam agents comprising perfluoropolyether compounds (PFPE). An automatic transmission fluid is provided containing the antifoam composition in a lubricating base oil, along with conventional additives such as antiwear agents. Automobile transmissions are provided that contain an automatic transmission fluid containing the new antifoam compositions. In a further embodiment, methods are provided for reducing unwanted noise in an automobile transmission during operation, comprising lubricating the transmission with an ATF containing the antifoam compositions of the invention.